Loss of the test piece back wall echo during scanning may be caused by:

Related MCQs

• When testing a test piece with parallel front and back surfaces, no back wall echo can be obtained. Which of the following actions might enable you to obtain a back wall echo?
• When using a straight beam technique to examine a thick test piece what change(s) would you expect to see in back wall echo size as you approach the side of the test piece? (Transducer remains completely on test piece)
• Compared to the echo returned from a smooth reflector, the echo returned from a natural flaw of the same area and orientation is:
• Echo amplitude losses may be caused by:
• When performing a post emulsifiable penetrant test, the test piece does not rinse acceptable clean during normal processing. What should be done?
• A soft aluminium test piece is to be penetrant tested. The piece has previously been sand blasted to remove tightly adhering soils. What additional surface preparation should be performed?
• Indications which are caused by design or construction of the test piece are called?
• ‘Undercut’ or ‘burned out’ edges of the test piece film image are caused by:
• A 50 percent decrease in echo amplitude is equal to a loss of how many decibels?
• Application of penetrant to a test piece may be by: